1. Field of the Invention
The present invention relates to an ophthalmic apparatus, and more particularly to an ophthalmic apparatus which examines and measures an eye to be examined, such as an apparatus for measuring an objective refractive power, an apparatus for measuring a corneal shape, and the like.
2. Description of Related Art
In conventional art, a setting-type apparatus is widely known as an ophthalmic apparatus such as an apparatus for measuring an objective refractive power, and the like. The setting-type apparatus is configured so that an examining-measuring part can be moved relatively to a fixation base. In generally, the setting-type apparatus is used by an examiner as following, firstly, the examiner makes the examining-measuring part move relative to an eye to be examined by operating a joystick or the like, then, makes the examining-measuring part be aligned with the eye, after that the examiner examines and/or measures the eye one by one. Therefore, referring to such ophthalmic apparatus, an interpupillary distance can be known by obtaining an amount of a lateral movement of the examining-measuring part at the time when condition is changed from which one eye is aligned to which the other eye is aligned. Further, whether the eye is a right eye or a left eye can be also known by detecting whether the examining-measuring part has moved to a right direction or a left direction relative to the center of the fixation base.
On the other hand, in case of using above mentioned setting-type ophthalmic apparatus, it is difficult to examine each eye of an infancy, that of a lying patient, that of an animal and the like, and it is inconvenient to bring it to another place, therefore, a handheld-type ophthalmic apparatus has been proposed recently. The handheld-type ophthalmic apparatus does not has a function to judge whether an eye is a right eye or a left eye based on a movement of an examining-measuring part though above mentioned setting-type apparatus has such function, therefore, whether the examiner examines and/or measures a right eye or a left eye is recognized by inputting a data indicating a right eye or a left eye with using a switch or the like.
However, an operation for inputting a data with using a switch in order to judge whether an eye is a right eye or a left eye is complicated, and the examiner sometimes forgets inputting a data, thereby resulting in a measurement error. In addition, in case of using a handheld-type apparatus, since an amount of a lateral movement while aligning can not be obtained, therefore, an interpupillary distance of the examinee could not be measured.